Pectin | definition of pectin by Medical dictionary Pectin | definition of pectin by Medical dictionary pectin [pek´tin] a one-sugar polymer of sugar acids of fruit that forms gels with sugar at the proper pH. A purified form from the rind of citrus fruits or from apple pomace is used as the protective component of formulations used in treatment of diarrhea and as a suspending agent in pharmaceutical preparations. It is also used in preparation of foods such as jams and jellies. pec·tin (pek'tin), Do not confuse this word with pecten. 1. Broad generic term for what are now more correctly called pectic substances or materials; specifically, a gelatinous substance, consisting largely of long chains of mostly d-galacturonic acid units (typically α-1,4 linkages and sometimes present as methyl esters), which is extracted from fruits where it is presumed to exist as protopectin (pectose). 2. Commercial pectins, sometimes called pectinic acids, are whitish, soluble powders prepared from the rinds of citrus fruits.

They are used in the preparation of jams, jellies, and similar food products where they increase viscosity; therapeutically, they are used to control diarrhea (usually in conjunction with other agents), as a plasma expander, and as a protectant; pectins bind calcium ions and are highly hydrated. pectin /pec·tin/ (pek´tin) a polymer of sugar acids of fruit that forms gels with sugar at the proper pH; a purified form obtained from the acid extract of the rind of citrus fruits or from apple pomace is used as an antidiarrheal and as a pharmaceutic aid.pec´tic pectin (pĕk′tĭn) n. Any of a group of water-soluble colloidal carbohydrates of high molecular weight found in ripe fruits, such as apples, plums, and grapefruit, and used to jell various foods, drugs, and cosmetics. pec′tic, pec′tin·ous adj.

pectin [pek′tin] Etymology: Gk, pektos, congealed a gelatinous carbohydrate substance found in fruits and succulent vegetables and used as the setting agent for jams and jellies and as an emulsifier and stabilizer in many foods. It also adds to the diet bulk necessary for proper GI functioning. See also dietary fiber . pectin Alternative health A soluble fibre found in fruits (e.g., apples, grapefruit and vegetables). Pectin is antidiarrhoeal, demulcent and used to soothe the mouth and throat, reduce colic and diarrhoea, and reduces LDL-cholesterol. Food industry A heterogeneous family of highly branched, highly hydrated and glucuronic acid-rich fruit-based polysaccharides used to produce gelling agents. pec·tin (pek'tin) Do not confuse this word with pecten. 1. Broad generic term for what are now more correctly called pectic substances or materials. 2.

Commercial pectins, sometimes called pectinic acids, are whitish, soluble powders prepared from the rinds of citrus fruits; to make jams, jellies, and similar food products where they increase viscosity; therapeutically, used to control diarrhea, as a plasma expander, and as a protectant. pectin a complex POLYSACCHARIDE often found as calcium pectate in plant cells where it is a component of the MIDDLE LAMELLA of the cell wall. When heated, pectin forms a gel which can ‘set’, a feature used in the making of jams. pectin, n pectin is a gummy polysaccharide constituent of the cell walls of plants that is used as a thickening agent in jams and jellies. Pectin's mucilaginous qualities are useful in treating diarrhea and high cholesterol and it may have beneficial effects on radiation sickness as well. pec·tin (pek'tin) Broad generic term for what are now more correctly called pectic substancesor materials; specifically, a gelatinous sub stance, which is extracted from fruits where it is presumed to exist as protopectin (pectose).

pectin a homosaccharidic polymer of sugar acids of fruit, which forms gels with sugar at the proper pH; a purified form obtained from the acid extract of the rind of citrus fruits or from apple pomace is used as a protectant and in cooking. Has a gelatinizing capacity and may be important in stabilizing the foam in frothy bloat. pectin methyl esterase a plant enzyme thought to have significance in the cause of bloat in cattle because of its role in the digestion of pectin and liberation of frothing agents pectic and galacturonic acids. What is pectin? | Baking Bites What is pectin? August 10, 2012 in Cooking , Ingredients 2 Comments Pectin is a naturally-occurring thickening agent that is most often used by adding it to jams, jellies and similar products to help them gel and thicken. Pectin creates a thick, clear set when it gels. It is a carbohydrate (a polysaccharide) found in and around the cell walls of plants, and helps to bind those cells together. All fruit has pectin in it, but the amount varies widely.

Apples and oranges contain the most pectin, and the pectin from both fruits is used commercially to thicken many different types of products. Pectin generally needs a high sugar content and some acid, such as citric acid, to activate, and some commercially available pectins include citric acid as an ingredient to help ensure that consumers get their desired result when working with their products. Pectin can be bought at the grocery store in both powder and liquid forms, and it can also be introduced to a recipe by adding fruit that has a high natural pectin content, such as apples or plums. Gelatin and pectin both produce clear gels with a high sheen, but the products are not the same. Pectin is a water-soluble fiber, while gelatin is a protein derived from animals. Pectin is used almost exclusively in high-sugar products, like jams. Gelatin, on the other hand, is used in a much wider variety of foods, including mousses, marshmallows and frostings because gelatin sets in a cool environment and does not require that specific ingredients be included to activate it.

Science of Cooking: Pectin & Preserves | Exploratorium Monthly Feature: A tubby glass jar filled with apricot jam sometimes stays on the table well beyond breakfast. In fact, we often deliberately leave it sitting, its rich glow beckoning, like a jar of bottled sunshine on a dismal February day. That jar is also a reminder, a fine dividend from our gathering and preserving tasks the previous summer. Local fruit, picked at peak condition and turned quickly into jams and jellies, offers an opportunity to experience the pleasures of "making your own." It's not just the act of capturing the flavors of summer that's appealing. Working with pectin has its own rewards, as anyone who has ever witnessed this fascinating substance transform hot fruit syrups into delicate gels could attest. Pectin is a carbohydrate found mostly in the skin and core of raw fruit. In nature, it functions as the structural "cement" that helps hold cell walls together. In solution, pectin has the ability to form a mesh that traps liquid, sets as it cools, and, in the case of jam, cradles suspended pieces of fruit.

Pectin needs partners, namely acid and sugar, to do the job of gelling properly. Acid helps extract pectin from fruit during gentle simmering and helps the gelling process, which will not take place unless the mixture is fairly acidic. If fruits (such as apricots) aren't sufficiently tart, a recipe will call for added lemon juice. Each month, we've featured a different kitchen science article by the Inquisitive Cooks, Anne Gardiner and Sue Wilson , with tips, facts, and unique ideas to give you a whole new perspective on cooking. View previous articles. Also visit Ask the Inquisitive Cooks for a weekly kitchen science Q&A! How do they make jellybeans shiny? Can the color of a candy affect the way it tastes? Do candy factories really look like Willy Wonka's? Join us as we investigate the sweet world of sugar. Sugar enhances the strength of the gel by attracting some of the water away from the pectin. In the absence of sufficient water, pectin molecules are more likely to unite with each other. Sugar also acts as a preservative, firms the structure of the fruit, and helps the jam or jelly hold its color and flavor.

If you're using commercial pectin, remember that each jam or jelly recipe is designed to maintain the correct balance between pectin, acid, and sugar for the fruit you're using. If you mess with the proportions, don't expect jam or jelly to set properly. Pectin content varies according to the type of fruit and its ripeness. Some fruits, such as apples, blackberries, grapes, and quince, are rich in natural pectin and therefore have an abundance of setting power. Fruits low in pectin are often combined with those high in pectin. Orange (high pectin) and rhubarb jam (low pectin) for instance, blends two fruits with quite different pectin contents. Or commercially packaged pectin can be added to fruits low in natural pectin, like apricots, rhubarb, and strawberries. Note that just-ripe fruit contains the highest pectin levels. When fruit ripens further, its pectin content decreases as pectin turns to pectic acid. Don't be overly impressed by advertisements for "jam berries" that imply that overripe mushy fruit is optimal for preserving.

Though in very ripe fruit, flavors are fully developed, pectin is often past its prime. For best results, mix fully ripe fruit, which has the best flavor, with just-ripe fruit, which has the highest gelling power. Give jam and jelly making a try this season. You'll not only enjoy the process, but come winter, you'll treasure your results! Anne Gardiner & Sue Wilson are the authors, with the Exploratorium, of the book The Inquisitive Cook. Protopectin | definition of protopectin by Medical dictionary Protopectin | definition of protopectin by Medical dictionary pectin [pek´tin] a one-sugar polymer of sugar acids of fruit that forms gels with sugar at the proper pH. A purified form from the rind of citrus fruits or from apple pomace is used as the protective component of formulations used in treatment of diarrhea and as a suspending agent in pharmaceutical preparations. It is also used in preparation of foods such as jams and jellies. pec·tin (pek'tin), Do not confuse this word with pecten. 1.

Broad generic term for what are now more correctly called pectic substances or materials; specifically, a gelatinous substance, consisting largely of long chains of mostly d-galacturonic acid units (typically α-1,4 linkages and sometimes present as methyl esters), which is extracted from fruits where it is presumed to exist as protopectin (pectose). 2. Commercial pectins, sometimes called pectinic acids, are whitish, soluble powders prepared from the rinds of citrus fruits. They are used in the preparation of jams, jellies, and similar food products where they increase viscosity; therapeutically, they are used to control diarrhea (usually in conjunction with other agents), as a plasma expander, and as a protectant; pectins bind calcium ions and are highly hydrated. pectin /pec·tin/ (pek´tin) a polymer of sugar acids of fruit that forms gels with sugar at the proper pH; a purified form obtained from the acid extract of the rind of citrus fruits or from apple pomace is used as an antidiarrheal and as a pharmaceutic aid.pec´tic pectin (pĕk′tĭn) n.

Any of a group of water-soluble colloidal carbohydrates of high molecular weight found in ripe fruits, such as apples, plums, and grapefruit, and used to jell various foods, drugs, and cosmetics. pec′tic, pec′tin·ous adj. pectin [pek′tin] Etymology: Gk, pektos, congealed a gelatinous carbohydrate substance found in fruits and succulent vegetables and used as the setting agent for jams and jellies and as an emulsifier and stabilizer in many foods. It also adds to the diet bulk necessary for proper GI functioning. See also dietary fiber . pectin Alternative health A soluble fibre found in fruits (e.g., apples, grapefruit and vegetables). Pectin is antidiarrhoeal, demulcent and used to soothe the mouth and throat, reduce colic and diarrhoea, and reduces LDL-cholesterol. Food industry A heterogeneous family of highly branched, highly hydrated and glucuronic acid-rich fruit-based polysaccharides used to produce gelling agents. pec·tin (pek'tin) Do not confuse this word with pecten. 1.

Broad generic term for what are now more correctly called pectic substances or materials. 2. Commercial pectins, sometimes called pectinic acids, are whitish, soluble powders prepared from the rinds of citrus fruits; to make jams, jellies, and similar food products where they increase viscosity; therapeutically, used to control diarrhea, as a plasma expander, and as a protectant. pectin a complex POLYSACCHARIDE often found as calcium pectate in plant cells where it is a component of the MIDDLE LAMELLA of the cell wall. When heated, pectin forms a gel which can ‘set’, a feature used in the making of jams. pectin, n pectin is a gummy polysaccharide constituent of the cell walls of plants that is used as a thickening agent in jams and jellies. Pectin's mucilaginous qualities are useful in treating diarrhea and high cholesterol and it may have beneficial effects on radiation sickness as well.

pec·tin (pek'tin) Broad generic term for what are now more correctly called pectic substancesor materials; specifically, a gelatinous sub stance, which is extracted from fruits where it is presumed to exist as protopectin (pectose). pectin a homosaccharidic polymer of sugar acids of fruit, which forms gels with sugar at the proper pH; a purified form obtained from the acid extract of the rind of citrus fruits or from apple pomace is used as a protectant and in cooking. Has a gelatinizing capacity and may be important in stabilizing the foam in frothy bloat. pectin methyl esterase a plant enzyme thought to have significance in the cause of bloat in cattle because of its role in the digestion of pectin and liberation of frothing agents pectic and galacturonic acids. Which Fruits Are High in Pectin? | Healthy Eating | SF Gate Which Fruits Are High in Pectin? Which Fruits Are High in Pectin? Citrus fruit is a rich source of pectin. Pectin is a type of water-soluble fiber found in a variety of fruits and vegetables.

Commercially, it’s used to make jams and jellies because it turns into a sticky gel-like compound when combined with water. Pectin’s sticky properties also contribute to your health by attaching to cholesterol-rich bile within your intestines and carrying it out of your body. Citrus fruits and apples are particularly rich sources of pectin. Benefits of Pectin Pectin is a type of carbohydrate -- specifically a polysaccharide -- that’s found in the cell walls of plants, especially the leaves, roots and fruits. It acts mainly to bind plant cells together. Pectin content varies widely among plants and even within the same plant over time. In general, pectin is broken down by enzymes as fruit ripens and becomes softer. Pectin and other dietary fibers do not contribute significantly to nutrition -- primarily because your intestines can’t digest them very well -- but they do contribute to health. Pectin consumption impacts blood cholesterol levels and it help regulates blood glucose levels. It also helps remove toxins such as lead and mercury from your body.

Citrus Fruit The fruits containing the most pectin are citrus fruits, especially grapefruits, lemons and oranges, according to a study published in a 1997 edition of the “Journal of Food Science.” The majority of the pectin resides in the citrus peel, but the pulp also contains some. In grapefruit pulp, the percentage of pectin ranges from 0.24 to 0.65 percent of weight. In comparison, lemon pulp contains about 0.63 percent pectin, and oranges range from 0.25 to 0.76 percent. To make a significant impact on blood cholesterol levels, approximately 6 grams of pectin needs to be consumed daily -- which is about four medium-size grapefruits weighing about 250 grams each. Apples Apples are also an excellent source of pectin. In practical terms, apples are often a better source than citrus fruit because most people eat the apple skins, which is where a significant proportion of the pectin resides. In contrast, the vast majority of people remove and discard the pectin-rich peel from citrus fruit.

The amount of pectin in apple pulp ranges widely, from 0.14 to 1.15 percent of weight. Variety, growing conditions and ripeness affect pectin content. Other Good Fruit Sources A number of other fruits are very good sources of pectin -- assuming you eat them with their skin -- and these include all berries, peaches, apricots, cherries and grapes. Berries particularly notable for their pectin content include strawberries, blackberries, raspberries and dewberries. Bananas are also a good source, especially if you don’t let them get too ripe or soft before eating them. Blueberry Kitchen Science – EAT it NOW or EAT it LATER January 10, 2016 Have you every wondered why your blueberry smoothies sometimes turn to jello when you let it sit?? That’s because ripe blueberries contain natural pectin, a substance found in fruits that help make the wonderful texture of jams and jellies. Pectin is a carbohydrate found in the cell walls of fruits and vegetables. When pectin is cooked with sugar and acid like lemon juice, it solidifies and becomes more solid.

Oddly unripe apples still have the most pectin than most fruit and are commonly used in addition to berries when making jam. I wanted to show you what happens when you use fresh ripe blueberries in smoothies. I added some blueberries in the blender and pureed it. Pour it into a cup and let it sit. This helps the pectin molecules bond to each other and causes a gelation of the liquid. Notice as soon as the blueberry mixture was poured out, it looks a lot like liquified jello! With some heat and a bit more acid and sugar, you can increase this effect. The heat causes the pectin to release from the cell walls and as it cools, the pectin molecules bond together. That’s why berry jam normally contains lemon juice and lots of sugar!! The next time you host a party, make some blueberry smoothies and serve them right away. Watch the reactions of the guests who don’t drink their smoothie right away!!

Check out other recipes on our blog Share this: Secret Garden Club: Jams, jellies and chutneys Friday, 1 November 2013 Jams, jellies and chutneys Smoking, drying and salting have all been used for hundred, indeed thousands, of years to preserve food. In the days before refrigeration and freezing, people relied on time-honoured methods for keeping food from spoiling. Using sugar is necessarily a more modern technique, given that we only started importing sugar cane in the 16th century and the sugar content of beet wasn’t discovered until the 1700s. It was the Victorians and then Edwardians who took preserving with sugar and elevated it to high art in the kitchen. They filled their larders with jams, jellies, catsups (ie, what we now call ketchups), syrups, pickles, and chutneys, all of which use sugar to a greater or lesser extent for its preservative properties. These days, we don’t really have the storage space of the big Victorian and Edwardian houses. And for many of us, we don't have much in the way of spare time.

With fridges and freezers, there simply isn't as great a need to find ways to keep food beyond its natural sell-by date. Instead we can concentrate on using time-honoured preserving methods to deal with a glut of produce or to create something different (and often superior) to the usual commercially prepared jams and jellies. Both jams and jellies rely on sugar and pectin for taste, consistency and ability to keep well. Pectin is a carbohydrate found in the cell walls of fruits and vegetables. It is a natural setting agent and it is the presence of pectin that makes jams and jellies thicken and set. Fruit jellies do nor (or should not) contain gelatin; they ‘gel’ through the presence of pectin. Some plants are richer in pectin than others. Strawberries, for example, are notoriously low in pectin and often strawberry jam needs to be made with sugar that has had pectin added to it. Apples are high in pectin and are often added to low-pectin fruits as another way of helping them to set, as are another high-pectin fruit, redcurrants.

Damsons, plums and quinces are naturally high in pectin and will thicken into jam or jelly relatively easily. Jams include whole or chunks of fruit. The liquor in which the fruit is suspended should be thick and syrupy, but not jellied. Jellies are strained and so contain no fruity lumps. A properly made jelly should be clear, not cloudy. Ideally a fruit jelly for spreading on toast or serving with meat should be less hard-set than a dessert jelly. The sugar added to jams and jellies acts as the preservative - without added sugar the fruit won't keep, nor of course will they taste so sweet. Sugar is currently public food enemy number one and there’s no doubt that we should probably all eat less of it . However, you can't significantly reduce the sugar content in a jam or jelly and maintain the same preservative effect. If the amount of sugar required makes your teeth itch, then by all means reduce the amount of sugar to your taste, but then store the preserve in the fridge and eat it all up within two weeks.

Chutneys are derived from the Indian ‘chutni’, or ‘chatni’ (think of the ‘chat’ that you can eat in an Indian restaurant today), a spicy relish eaten as a side dish or accompaniment. Indian chatnis or relishes tend to be more spicy and savoury – and always vegetarian. When the British first encountered them in early Colonial days and brought them home and adapted them, it was the sweet and fruity aspect of chutneys they enjoyed. So our chutneys, as opposed to chutnis, tend to be sweeter, and less fiery - more of a cross between a jam and a pickle. Chutneys rely on both sugar and vinegar (and salt, to some extent) to preserve their ingredients. General tips for making jams, jellies and chutneys Use copper, steel or aluminium pans for making sugar-based preserves. Enamel pans are fine so long as they are not chipped. Use non-reactive, ie, not copper or aluminium, pans for vinegar-based pickles. Pick or choose fruit that is exactly ripe. Overripe and your jam or jelly might ferment. Underripe and it will lack flavour and will need more sugar.

Don’t used the blemished parts of fruit. It will impair the flavour. Don’t pick fruit when it’s wet. It will be waterlogged and your jam/jelly will be weaker in flavour, and might go mouldy. Jams and jellies should be cooked until they are just set - test the liquid frequently to ensure that you don't overcook. Chutneys need to be cooked long and slow so that the ingredients soften and the flavours have plenty of time to blend. The jars you use to store the preserves in should be sterilised. This is not a complicated process. The easiest way to sterilise jars (and their lids) is to put them through a dishwasher cycle (not a low temperature, or economy setting) and then into an oven at 120 degrees to dry off. Alternatively, you can wash, then rinse the jars in very hot water, and dry off in the oven as above. You can sterilise in the microwave by filling jars half-full with water and heating on high for 2 minutes. Empty the jars and dry in the oven as above. The jars should have properly fitting, airtight lids, which should also be sterilised in hot soapy water, rinsed and dried.

Your jams, jellies and chutneys should be stored in a cool, dry, dark place. Once opened, keep them in the fridge. Chutneys should be stored for at least three months before eating, so that the flavours can blend and mellow properly. I've been lucky enough to have a glut of quinces from the tree this year - nearly 200 hundred plump quinces each weighing around 300g or more. The blossom on quince trees doesn't appear until May, by which time the weather had warmed up and it stayed warm throughout the summer - perfect conditions for developing and setting plenty of fruit. Quince jelly is a great way to may the most of quinces when they are plentiful. It's a simple jelly to make, it cooks to the most beautiful clear amber colour and the resulting jelly is delicious, whether spread on bread or toast, or eaten to accompany meats or cheese. Furthermore, if you go on to make quince cheese (quince paste or 'membrillo') with the same quinces, you get two sweetstuffs for the price of one: the jelly from the juice and the membrillo from the pulp.

Quince jelly The first stage with any jelly is to extract the juice. We do this without any sugar added at this stage. Chop up the fruit. Don’t peel it or core it – the peel and pips contain lots of valuable pectin. Do remove any blemishes, stalk or leaves. Put the chopped pieces in a big non-reactive pan and add lemon juice and lemon zest – about one lemon for every 1.5kg or 3lbs of chopped fruit. Then add water: 2 litres for every 1.5kg of fruit, although here I tend to think in imperial measurements and add a pint of water for every pound of fruit. Bring this to the boil and simmer away for about an hour and a half. You can use a potato masher to push the fruit down in the water and make sure lots of flavour is released. At the end of an hour and a half, the fruit should be very soft and mushy. Next you need to strain the fruit juice. Traditionally people suspend a jellybag made with a muslin square over a bowl and let the juice drip through.

You can buy special jelly bags and stands, but I still like the old-fashioned method of turning a chair upside down on top of another chair and tying a big colander to the upturned legs and draping my muslin over the colander. My mother-in-law rigs up something similar using the clothes horse - another traditional piece of equipment in its own right. Whichever way you use, give your fruit mix several hours, preferably overnight, to strain, and don’t, whatever you do, try to speed the process up by pressing down on the colander. This will give you cloudy jelly. What you are left with after straining quinces is an opaque pink juice, which is used for making jelly, and the quince pulp, which can be used to make membrillo. The next stage is to boil this juice up with sugar until it sets into a jelly, then pour it into sterilised jars. Start sterilising your jars by whichever method you favour. Get a cold plate and a teaspoon and place these near the hob on the worktop. Have a tea strainer, mesh spoon, or shallow spoon handy for skimming. Measure the amount of juice you have.

For every 600ml of juice, you need 450g of sugar. Pour the juice into a large pan and add the sugar. Stir over a low heat to dissolve the sugar, then turn the heat up to bring the juice up to the boil. From this point on, you need to keep a careful eye on the pan. The syrup should be maintained at a good rolling boil, so that it looks pale and almost foamy as it bubbles away. This is one process where a gentle simmer won't do. On the other hand, you don't want it to bubble up so fast that it boils over. When the liquid boils up, you'll see a white residue, like froth, or even something more solid, forming on the surface. This needs to be skimmed out of the jelly, either with a spoon, or a strainer. I find sweeping a tea strainer through the top of the liquid is an effective way to do it. How long you need to boil the syrup for will vary from batch to batch. I would usually expect around 20 minutes of good, hard boiling, but it could be less and is quite often longer.

Test your liquid initially after about 5 minutes to get an idea of how it's progressing, but don't expect anything like a set at this stage. To test manually, dip your teaspoon into the pan and drop a spoonful of the liquid on to the cold plate. Leave it to cool, then push your forefinger through the little pool of liquid on the plate. If it feels syrupy, if the surface of the liquid wrinkles at all as you push your finger through it, and if the the two sides of the liquid stay separated instead of pooling together again after you have lifted your finger again, the your jelly is set and ready to pour into jars. So, do your first 5 minute test, then test again after 5 minutes. This second test should look much more syrupy, but you probably won't get that tell-tale wrinkling of the surface of the liquid on the plate. From now on, it's a good idea to take your pan off the heat when you test. You don't want to find you've achieved your set with the pan still merrily bubbling away, as it carries on cooking your jelly. Once your liquid starts to look syrupy, test every 2-3 minutes.

When you think it has set, let the bubbles in the pan die down and skim again so that you are left with a clear amber syrup. Have your warm sterilised jars ready and a ladle and, if you have one, a jam funnel (an ordinary funnel will be just as useful). Spoon the syrup carefully into the jars and cover with the lids. Leave to cool, then tighten the lids fully. Label the jars and store somewhere cool and dark. Quince cheese Take the soft chunks of quince left over after straining for jelly, above, and push through a sieve, or, less arduously, a mouli-legumes. I find that if you use a mouli and start with the disc with the largest holes, then pass the puree you get from that through the smallest disc, you will get a fine quince puree for rather less elbow grease than trying to get the pulp through a sieve straightaway. Whichever method you use it's still hard labour. Don't be tempted to puree in the food processor, though, you want to sieve out the pips and skin and core, not pulverise them.

Weigh the final puree, put in a heavy-bottomed pan (a wide, non-stick pan is a Godsend), and add the same amount in weight in sugar. So, if you have 1kg of quince, add 1 kg sugar. Stir over a medium heat until the sugar dissolves, then bring to the boil - the puree will pop and bubble. It's rather like looking into the crater of an active volcano. Keep stirring and keep the mixture on the boil. The colour will deepen from pale orange to a deep rich reddish-brown. The puree will thicken and eventually - it may take up to an hour - you will be able to draw your spoon along the bottom of the pan and the mixture will be stiff enough to stay separate in the pan. Remove from the heat. You can store quince cheese in small wide-topped pots, or spread out on greaseproof paper to cut into shapes when it's cool and fully set. If using pots, dampen a piece of kitchen paper with a little vegetable oil and rub it around the base and sides. This will make it much easier to unmould the cheese later.

I use the little plastic pots which the local Chinese takeaway uses for your dipping sauces - they're just the right size and shape. Leave to cool completely, then store somewhere cool and dark or in the fridge. Quince cheese seems to keep forever. Posted by Compound Interest - What Makes Jam Set? – The Chemistry of Jam-Making What Makes Jam Set? – The Chemistry of Jam-Making click to enlarge If you’ve ever tried your hand at jam-making, you’ll know that it’s something of a tricky process. A number of factors need to be just right to achieve a perfectly set jam – and chemistry can help explain why. There are three key chemical entities that go into jam-making: sugar, pectin, and acids. Here, we’ll look at each in turn, and how they help jam achieve its eventual consistency. Pectins Pectins are long, linked chains of sugar molecules, which are found naturally in plant cell walls. Although we refer to them in general as ‘pectin’, their structures are variable, as well as hard to determine; a rough general structure is given in the graphic, but in reality the overall structure can be much more complicated. Pectins are found in fruits, particularly in the peels and cores.

When jam sets, pectin plays a vital role. Boiling the jam releases the pectins from the fruit used; with the correct amount of sugar and acidity, which we’ll discuss in due course, the long pectin chains can bind to each other via intermolecular interactions, forming a gel network. This network generally forms at the ‘setting point’ of jam, which is approximately 104˚C. Once it has formed, the jam can be allowed to cool, and the gel network ‘traps’ the water content of the jam, leading to setting. The pectin content of different fruits varies: fruits such as apples and blackcurrants have higher levels of pectin than those such as strawberries and raspberries. In cases where a jam is being made from a low pectin fruit, either a higher pectin fruit must also be included, or commercial pectin must be added. Commercial pectin is obtained from the peel of citrus fruits, which have a naturally high pectin content. Sugar An important part of jam is, of course, the sugar content, which is vital for the flavour and also plays a role in helping jam set.

Many jam recipes recommend the use of a 1:1 ratio of fruit to sugar in jam-making. As well as sweetening the jam, the sugar also helps the pectin set – it enhances the pectin’s gel-forming capability by drawing water to itself, decreasing the ability of the pectin to remain in separate chains. Additionally, sugar imparts a preservative effect. By binding water molecules to itself, it reduces the amount of water available in the jam, to the point at which it is too low for microbial growth, helping to ensure that the jam doesn’t go off too rapidly after it’s been made! The final sugar content of jam should be between 65-69%. Acids Acids are also important in helping the pectin to set. The COOH groups in the pectin are usually ionised, and the negative charges on the molecules this ionisation causes can cause repulsion, and prevent the pectin chains from being able to form the gel network. To avoid this, we need the pH of the mixture to be roughly in the range of 2.8-3.3.

At these more acidic pHs, the COOH groups aren’t ionised, lowering the magnitude of the repulsive forces. Fruits naturally contain acids – the most well known is citric acid, but malic acid and tartaric acid are also found in a number of fruits. Whilst some acid will be contributed by the fruit from which the jam is made, often this won’t be enough to reach the desired pH, and for this reason more must be added. This is commonly in the form of lemon juice, which contains citric acid, though powdered forms of acids can also be used. In summation, then, the three factors of pectin, sugar and acid have to be in perfect balance for jam to set. If it doesn’t, you can often point to one of those three factors being somehow amiss – and understanding the chemistry behind why jam sets in the first place can often help you identify how to fix it! A modified version of this graphic will be included in the upcoming book “Why Does Asparagus Make Your Wee Smell?”, available to pre-order now ! What is Pectin? (with pictures) What is Pectin?

Last Modified Date: 25 December 2016 Copyright Protected: 10 hilariously insightful foreign words In cooking, pectin is used as a thickening agent, and could be considered one of the most natural types around. The first version of this substance available for purchase was derived from apples, which have a high amount of it. There are other fruits that naturally contain this gelling agent, including many plums and pears. The properties of pectin were discovered and identified by the French chemist and pharmacist, Henri Braconnot, and his discovery soon led to many manufacturers making deals with makers of apple juice to obtain the remains of pressed apples (pomace) that were then produced in a liquid form. Pectin is a complex carbohydrate, which is found both in the cell walls of plants, and between the cell walls, helping to regulate the flow of water in between cells and keeping them rigid. You’ll note some plants begin to lose part of this complex carbohydrate as they age. Apples left out too long get soft and mushy as pectin diminishes.

Ad This is great news for people who are having extended trouble with irritable bowel syndrome or are getting over a bout of diarrhea because the presence of this substance in apples is considered some of nature’s best medicine. Doctor’s frequently prescribe the brat diet for patients with this condition (bananas, rice, applesauce and toast). Either whole apples or applesauce can help end these nasty stomach conditions by providing that extra thickening agent in the gut. In fact, one of the leading medications for this problem, Kaopectate®, used pectin as one its main “active” ingredients, though the ingredients changed in 2002. You will find this thickening agent in other medications. Luden’s® uses it as a main ingredient in many of its cough drops. Cosmetic companies also make use of the ingredient, particularly when they’re looking for natural or non-animal alternatives to bind substances together. More often, though, you’ll find pectin available in powdered form to be used when making jams and jellies. Today it may be made from apple pomace or from orange peels, and it’s usually available in powdered rather than liquid form.

It doesn’t add flavor to the dishes you use it in, and it does work extremely well as a thickening agent. This complex carbohydrate is also used in a variety of commercially prepared foods to bind these foods together more effectively. You’ll find it in products like yogurt , chocolate milk, and in a number of commercial baked goods. Ad Can I use pectin by itself for health purposes? myharley Post 8 After all these years of using pectin as a thickening agent for making jellies and jam I never knew it was made from fruit. I guess I never stopped to wonder what it was made from. I just know that when I get ready to make a batch of jelly, I need to use pectin. I have always used the powdered pectin, but I have also seen liquid pectin for this purpose too. Since I have always had good results using the powder form, I will just stick with that. I would be frustrated if I tried something different and my jelly didn't turn out right. LisaLou Post 7 I am most familiar with pectin when I use it when making my strawberry jam.

I usually find this in the baking aisle of my grocery store but sometimes in spring when the strawberries are in season they are sold out. It can be kind of tricky to get just the right amount of pectin when making jam. If it turns out too runny, I know I didn't add quite enough pectin. sunshined Post 6 @anon270741-- That is encouraging to know your IBS is under control. Hopefully eating the apples is one of the reasons why. There must be a lot of truth to that old saying that an apple a day keeps the doctor away. I also have IBS but never realized that eating apples could be so beneficial for this condition. For the most part I eat a pretty bland diet and this seems to keep the IBS from flaring up. anon270741 Post 5 I have IBS and eat a few apples (including the seed and everything else except the end core). At the moment the IBS is well under control. anon137349 Post 4 Pectin absorbs lead from your blood through your gut so the lead won't cause damage to your brain,heart and other soft organs or deposit in your bones.

Lead causes ADD and ADHD so pectin might help people with neurological damage from lead exposure. Lead exposure also causes colon cancer so pectin might help to prevent colon cancer. An apple a day will keep the doctor away! jsw23 Post 3 @cmsmith10- In addition to the benefits pectin provides for the skin, pectin is also used to lower blood lipoprotein levels. High levels of lipoproteins can result in clogged arteries, so the pectin essentially assists in lowering risk of heart disease. As the article mentions, pectin is a crucial aspect of jam making. I tried my hand at mulberry jam a few months ago and neglected to use the gelling agent. The end result was watery, smashed berries with tons of sugar collected at the bottom of each jar. Definitely include pectin to ensure a thick consistency for fruit spreads. cmsmith10 Post 2 If you want to freeze your fruit, adding pectin to it (fresh fruit or boiled) before freezing it, helps maintain its texture when frozen and then thawed. Also, fruits high in pectin are highly beneficial to firm and tone skin. One at-home recipe is for facial toner.

Boil a small green apple (remove seeds and cube the apple) and a half cup of water. Once cooked, remove your apples from heat and allow them to cool. Strain this through a mesh strainer. Add about a fourth of a cup of witch hazel to it. Mix it all together and dab it onto a cotton ball and apply to your face. Works great! Post your comments

Question: What is the name of the carbohydrate found in the cell walls of fruits and used in the setting of jams and jellies?
Answer: PECTIN